THE STUDY INCLUDES THE FOLLOWING: 1.Improve our understanding of the natural course and pathogenesis of retinal and choroidal lesions of benign and malignant hypertension. This is accomplished by detailed serial studies documented by stereo fundus photographs and fluorescein angiograms. These studies will be supplemented by clinicohistopathologic correlations using serial paraffin sections, trypsin digest preparations of retinal vessels, electromicroscopy as well as the use of animal (primate) model. 2. Develop a simpler and more acceptable classification of hypertensive retinopathy to improve aspects of the 30-year-old Keith-Wagener Classification. This study is of utmost importance since it will serve as a guideline for understanding the severity, duration, prognosis and effectiveness of therapy of hypertension, a disease which afflicts approximately 25 million Americans. 3. Obtain additional information about the basic mechanisms of retinal and choroidal vascular disorders which may be relevent to the understanding of some nonhypertensive vascular fundus lesions. 4. Delineate ocular complications of long-term immunosuppressive therapy, particularly the relationship of corticosteroids and cataract formation.